Called "Independent monitor", EC-7915 (or 7950) was a
complete terminal with Z80 CPU and firmware allowing to do basic things
in text buffer. It was made on Swedish licence - in Sweden it was known
as Stansaab Alfaskop. It was quite rough construction even in 1980s, as
Mera purchased licence in 1976 or 77. 7915 was expensive, but it used no
other circuits than simple logic and EPROMs. Later models had 8255
circuit to control keyboard, allowing to drop Keyboard Module. The
device used amber CRT, and was complete Z80 system working in modular
technology - module for CPU and data processing, module for text output,
in earliest models (I don't know if these were made outside Sweden)
module for keyboard handling.
These units were used with many computers, starting from Mera 60 RT
system up to ComPAN 8 CP/M machine.

Peripherals in collection:
- Keyboard - NOT original one, or too much original - from
German terminal (also western Mini Bee Terminal,
keyboard manufactured by Micro Switch as SW1139, see
schematic), which was
used with first units of Mera and abandoned because
of rare parts used.

My unit comes from Cracow's
waterworks authority. It was used there probably with Mera 60
computer (see picture). As they dismantled the computer, they
removed back cover to disconnect keyboard - it's missing.
My unit isn't in good condition - as logic part works perfectly, the
display is heavily damaged. Centering rings on CRT are shattered
and some CRT circuitry is bad too. As I tried to diagnose it (I
don't have a schematic) I figured out that there may be problems
with CRT filament voltage or the CRT itself.

Mera-60 was a RT computer system for industrial measurements. It was
based on 8080 CPU, battery-backed RAM and had modular
construction allowing to install additional interfaces (digital,
such as DZM-180 printer interface, 1.8MB 8" floppy disk
controllers or digital measurement inputs, counters, static
inputs etc.), RAM, EPROMs, paper tape reader/puncher etc.
It was
working in Bosman operating environment (it has nothing in
common with Bosman 8 CP/M machine!) had built-in text editor,
assembler and MacroBasic interpreter.
It had also Logel language (not to be confused with Loglan
Pascal-like language invented by the end of 1970 in Warsaw
University and implemented in Mera 400 computer), a process modelling language
invented in Poland. It was used to program parts of Mera-60/80
system, and resulting binary code was burned to EPROMs of Mera
system. If you want to analyse binaries, you can download a few
pieces of it
here.
The first step in Logel modelling, was to design the model using
Logel tools: dependency tables, logic expressions/schemmas and
consecutivity diagrams. The program was compiled on JS
(Jednolity System - Unified System, not JavaScript!) computers
and resulting binary code was punched on paper tape. This tape
was fed to Mera 60/80 system, which burned its EPROMS with the
code. These EPROMS were used to drive a whole industrial system.
There were "single" and "double" cards, "double" ones had twice
more 2716 EPROMS and manual switch to switch banks. It allowed
to, for example, change supervised process very quickly, which
was useful where different shifts manufactured different things
on the same production line.

Later terminals had Czechoslovakian keyboard made by Konsul Zbrojovka
Brno, which was similar to Alfaskop 3500's. Early units, shipped with
Mera 60 or 80, had Polish one, enclosed in case similar to Meritum computer.
First ones used Western German keyboards manufactured under
American brand Micro Switch and used in some American terminals.
Meritum took the casing from it.

After Elzab bought licence to manufacture these units, they became
wide-spread across Eastern block countries. Similar units were made in
Hungary, in Czechoslovakia (Tesla) and in Soviet Union.

Mera 60(source: Mera catalogue)

Mera 60(source: "1000 słów o komputerach i informatyce")

Original Alfaskop
(source: Frigoscandia catalogue)

Picture on the right shows modular-type
terminal used with Odra 1305. It's later one, with Zbrojovka
keyboard. The printer-keyboard unit is probably D-180KSRE or
similar. These "printing terminals" were used with Odra machines
and other applications.